How to convert Excel to JSON
- Drop an .xlsx, .xls, .ods or .csv file.
- Keep First row is a header ticked to use the column titles as JSON keys.
- Pick the sheet and click Download JSON.
The output format
With a header row, you get an array of objects: [{"Name":"Ann","Age":31}, …], which is what most JavaScript, Python and no-code tools expect. Without a header, you get an array of arrays, one per row. Numbers stay numbers, dates are written as ISO strings (YYYY-MM-DD) and empty cells become empty strings, so every object has the same keys.
Developers use this to seed databases and mock APIs, translators to move string tables into code, and analysts to feed spreadsheets into scripts. Headers with spaces or punctuation are kept as they are; rename columns in the spreadsheet if you need tidy keys such as first_name. Everything runs locally in your browser.
FAQ
What happens to empty header cells?
They become keys named col1, col2 and so on.
Are dates converted correctly?
Yes. Cells formatted as dates in Excel are written as ISO date strings.
Can I convert every sheet?
Download each sheet separately using the sheet tabs.